U.S. patent number 8,639,400 [Application Number 13/837,547] was granted by the patent office on 2014-01-28 for altitude control of an indoor flying toy.
This patent grant is currently assigned to Silverlit Limited. The grantee listed for this patent is Silverlit Limited. Invention is credited to Kwok Leung Wong.
United States Patent |
8,639,400 |
Wong |
January 28, 2014 |
Altitude control of an indoor flying toy
Abstract
Altitude control of a toy flying vehicle intended for indoor
hovering flight comprises providing a selected altitude level for
the vehicle. A position control signal is transmitted from the
vehicle towards a surface. A receiver in the vehicle receives the
signal reflected from the surface. A level of the reflected signal
by the receiver is determined, and a change of the reflected signal
is an indicator of a change of altitude of the vehicle relative to
the selected altitude level. The vehicle receiver communicates with
the remote controller, and the remote controller can adjust and
control speed and direction of the vehicle. Controlling the
altitude can be by a stop control; an up and/or down control;
and/or a high and/or low height sensitivity control,
take-off/landing control; gesture mode control; left/right trim
control; control between altitude control mode and manual control
mode.
Inventors: |
Wong; Kwok Leung (Causeway Bay,
HK) |
Applicant: |
Name |
City |
State |
Country |
Type |
Silverlit Limited |
Causeway Bay |
N/A |
HK |
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|
Assignee: |
Silverlit Limited (Causeway
Bay, HK)
|
Family
ID: |
49182077 |
Appl.
No.: |
13/837,547 |
Filed: |
March 15, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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13627948 |
Sep 26, 2012 |
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Current U.S.
Class: |
701/4; 701/301;
446/36; 244/76R; 701/16; 244/17.13; 701/300 |
Current CPC
Class: |
A63H
27/12 (20130101); A63H 30/04 (20130101) |
Current International
Class: |
A63H
27/133 (20060101) |
Field of
Search: |
;701/4,5,9,11,16,300,301
;244/17.11,17.13,76R |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1 354 220 |
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Oct 2003 |
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EP |
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2820216 |
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Aug 2002 |
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FR |
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2009279368 |
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Dec 2009 |
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JP |
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WO 02/059646 |
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Aug 2002 |
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WO |
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WO 03/067351 |
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Aug 2003 |
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WO |
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Primary Examiner: Black; Thomas
Assistant Examiner: Nolan; Peter D
Attorney, Agent or Firm: Greenberg Traurig, LLP
Parent Case Text
RELATED APPLICATION
This application is continuation-in-part of U.S. patent application
Ser. No. 13/627,948, filed Sep. 26, 2012 entitled ALTITUDE CONTROL
OF AN INDOOR VERTICAL FLYING TOY. This application is incorporated
by reference in its entirety.
Claims
The invention claimed is:
1. A method of remote controlling an altitude of a toy flying
vehicle intended for indoor operation, the vehicle having a rotor
for rotation relative to a fuselage of the vehicle, and a separate
remote controller for use by a player of the toy, the method
comprising: (a) providing a relative selected altitude level r'd
corresponding to a selected altitude for the vehicle; (b)
transmitting a position control signal with a light intensity I
from the vehicle towards a surface; (c) determining if a reflected
signal of said position control signal is received from the
surface; (d) increasing a counter CNT if said reflected signal is
received; (e) increasing said light intensity I; (f) repeating
steps (b)-(e) while said light intensity I is less than a maximum
value; (g) determining a relative altitude r' and adjusting rotor
action according to a difference between the relative altitude r'
and the relative selected altitude level r'd to retain the selected
altitude, wherein said determining the relative altitude r'
comprises selecting the relative altitude r' from a table
comprising correlations between values for the relative altitude r'
and values for the counter CNT; and controlling the toy by a
control selected from at least one of a stop control; an altitude
control by at least one of an up control; down control; a high
height sensitivity control and a low height sensitivity control;
take-off/landing control; gesture mode control; left/right trim
control; control between altitude control mode and manual control
mode.
2. A method as claimed in claim 1 wherein the selected altitude is
a range between an upper and a lower level.
3. A method as claimed in claim 1 wherein the selected altitude is
a substantially constant altitude.
4. A method as claimed in claim 1 wherein adjusting the rotor
action is to lower the speed to lower the vehicle to the selected
altitude or to increase the speed to raise the vehicle to the
selected altitude.
5. A method as claimed in claim 1 wherein the vehicle includes a
receiver for communication with the remote controller, the remote
controller being capable of adjusting and controlling speed and
direction of the vehicle.
6. A method as claimed in claim 1 wherein the position control
signal is directed upwardly thereby to retain the selected altitude
relative to a surface located above the vehicle.
7. A method as claimed in claim 1 wherein the surface from which
the signal is reflected is passive indoor surface.
8. A method as claimed in claim 1 wherein the position control
signal is directed downwardly thereby to retain the selected
altitude relative to surface located below the vehicle.
9. A method as claimed in claim 1 further including transmitting a
position control signal directed transversely relative to the
vehicle thereby to reflect from a transversely located surface
relative to the vehicle thereby to retain a distance of the vehicle
relative to the transversely located surface.
10. A method as claimed in claim 1 further including transmitting
multiple position control signals directed transversely in multiple
respective directions relative to the vehicle thereby to reflect
from multiple transversely located surfaces relative to the vehicle
thereby to determine one or more respective relative distances of
the vehicle to the multiple transversely located surfaces, and
thereby maintain the vehicle at one or more respective selected
distances to the transverse surfaces.
11. A method as claimed in claim 10 wherein the multiple position
control signals are directed relatively transversely, forwardly and
sideways of the vehicle.
12. A method as claimed in claim 1 including multiple position
control signal directed transversely in multiple respective
directions relative to the vehicle thereby to reflect from multiple
transversely located surfaces relative to the vehicle thereby to
determine one or more respective relative distances of the vehicle
to the multiple transversely located surfaces, wherein the multiple
position control signals are directed relatively transversely,
forwardly and sideways of the vehicle, and thereby maintain the
vehicle at one or more respective selected distances to the
transverse surfaces, and including signals directed upwardly and
downwardly from the vehicle thereby to maintain the selected
altitude of the vehicle.
13. A method as claimed in claim 1 further including defining a
desired selected level of reflected position control signal in at
least one receiver in the vehicle, and wherein the action of the
rotor is dependent on variation from a designated position, as
determined by a difference in the received reflected position
control signal.
14. A method as claimed in claim 1 including defining respective
desired selected levels of reflected position control signals in
multiple respective receivers in the vehicle, the respective
multiple receivers being directed in respective different
directions and there being multiple respective position signals
directed in mating respective directions relative the respective
receivers, and wherein the action of the rotor is dependent on at
least one variation from at least one designated position, as
determined by at least one difference in the received reflected
position control signals.
15. A method as claimed in claim 1 wherein the vehicle is
configured to limit the maximum height thereby to receive at least
one reflected signal.
16. A method as claimed in claim 1 including controlling rotor
power by current speed of the-rotor at a time (t) determined by a
previous speed at a time (t-1), and a battery level in the
vehicle.
17. A method as claimed in claim 1 wherein the level of the
reflected signal is a received digital measure and not an intensity
of the received signal.
18. A method as claimed in claim 1 wherein the vehicle comprises a
receiver to receive throttle and direction control commands from
the remote controller.
19. A method as claimed in claim 1 wherein adjusting the rotor
action according to a difference between the relative altitude r'
and the relative selected altitude level r'd comprises calculating
an error, E=r'-r'd, wherein if E is negative, representing a
current altitude of the vehicle as lower than the selected
altitude, the rotor increases the power for flying upward in which
the power increment is proportional to E; wherein if E is positive,
representing a current altitude of the vehicle is higher than the
selected altitude, the rotor decreases the power for flying
downward in which the power decrement is proportional to E, and
wherein if E is zero or approximate zero, representing the current
altitude of the vehicle is same as the selected altitude, the power
of the rotor remains unchanged.
20. A method as claimed in claim 1 wherein the selected altitude is
set by setting a throttle level from a transmitter.
21. A method of remote controlling an altitude of a toy flying
vehicle intended for indoor hovering flight, the vehicle having a
rotor for rotation relative to a fuselage of the vehicle, and a
separate remote controller for use by a player of the toy
comprising: (a) providing a relative selected altitude level r'd
corresponding to a selected altitude for the vehicle; (b)
transmitting a position control signal with a light intensity I
from the vehicle towards a surface; (c) determining if a reflected
signal of said position control signal is received from the
surface; (d) increasing a counter CNT if said reflected signal is
received; (e) increasing said light intensity I; (f) repeating
steps (b)-(e) while said light intensity I is less than a maximum
value; (g) determining a relative altitude r' and adjusting the
rotor action according to a difference between the relative
altitude r' and the relative selected altitude level r'd to retain
the selected altitude, wherein said determining the relative
altitude r' comprises selecting the relative altitude r' from a
table comprising correlations between values for the relative
altitude r' and values for the counter CNT; (h) performing steps
(a)-(g) for an additional position control signal directed relative
to the vehicle thereby to reflect from an additional located
surface relative to the vehicle thereby to retain the distance of
the vehicle relative to the additional located surface; the vehicle
being configured for communication with the remote controller, the
remote controller being capable of adjusting and controlling speed
and direction of the vehicle and a receiver in the vehicle being
responsive to signals with the remote controller, the signals from
the remote controller being for changing speed and direction of the
vehicle, and wherein the position control signal is directed
upwardly thereby to retain the selected altitude relative to
surface located above the vehicle, and wherein the surface from
which the signal is reflected is a passive indoor surface; and
controlling the toy by a control selected from at least one of a
stop control; an altitude control by at least one of an up control;
down control; a high height sensitivity control and a low height
sensitivity control; take-off/landing control; gesture mode
control; left/right trim control; control between altitude control
mode and manual control mode.
22. A method as claimed in claim 21 wherein adjusting the rotor
action according to a difference between the relative altitude r'
and the relative selected altitude level r'd comprises calculating
an error, E=r'-r'd, wherein if E is negative, representing a
current altitude of the vehicle as lower than the selected
altitude, the rotor increases the power for flying upward in which
the power increment is proportional to E; wherein if E is positive,
representing a current altitude of the vehicle is higher than the
selected altitude, the rotor decreases the power for flying
downward in which the power decrement is proportional to E; and
wherein if E is zero or approximate zero, representing the current
altitude of the vehicle is same as selected altitude, the power of
the rotor remains unchanged.
23. A method as claimed in claim 21 wherein the selected altitude
is set by setting a throttle level from a transmitter.
24. A system of remote controlling an altitude of a toy flying
vehicle intended for indoor operation, the vehicle having a rotor
for rotation relative to a fuselage of the vehicle, and a separate
remote controller for use by a player of the toy, the system
comprising a processor, a transmitter, a receiver, and a
non-volatile computer readable medium comprising executable
instructions which, when executed by the processor, cause the
system to perform the following method: (a) providing a relative
selected altitude level r'd corresponding to a selected altitude
for the vehicle; (b) transmitting a position control signal with a
light intensity I from the vehicle towards a surface; (c)
determining if a reflected signal of said position control signal
is received from the surface; (d) increasing a counter CNT if said
reflected signal is received; (e) increasing said light intensity
I; (f) repeating steps (b)-(e) while said light intensity I is less
than a maximum value; and (g) determining a relative altitude r'
and adjusting rotor action according to a difference between the
relative altitude r' and the relative selected altitude level r'd
to retain the selected altitude, wherein said determining the
relative altitude r' comprises selecting the relative altitude r'
from a table comprising correlations between values for the
relative altitude r' and values for the counter CNT.
Description
BACKGROUND
This disclosure relates to a flying vehicle and more specifically
to a hovering vehicle that includes a control system to
automatically control the height of the vehicle relative to a
surface or another object.
The control method is basically related to the distance
measurement. Some flying toys handle it with ultrasonic sensor. A
MCU connects to this sensor; it starts the timer while emitting a
pulse train from the sensor. MCU then measures the time elapsed of
reflected signal from the ground surface. As the speed of sound is
known, the distance travelled can be calculated. The limitation of
this application is that this sensor is comparatively large and
heavy for putting into a small flying toy with size less than 250
mm in length.
Alternatively, precise pressure sensor can be used to level the
absolute altitude for both indoor and outdoor flying toys but the
solution cost is too high to be applied in toys market and the data
is drifted from time to time.
SUMMARY
In present disclosure, a control method is used to maintain stable
altitude control of an indoor vertical flying toy such as
helicopter or multi-rotor copter. With this altitude hold function,
it is easy for beginners to have hover fight and it can avoid the
flying toy from being crashed to the ceiling if they are not
familiar with throttle control.
By being able to define and retain the distance from a ceiling
below which the craft should fly or hover a significant advantage
is attained with the method, system, and toy of the disclosure.
Further features can include one or more of an emergency stop
control which can be in the sense of a control button; an up and/or
down control which can be a single or multiple control button; and
a high and/or low height sensitivity control, take-off/landing
control; gesture mode control; left/right trim control; control
between altitude control mode and manual control mode.
Many advantages and features of the disclosure will become readily
apparent from the following detailed description of the disclosure
and the embodiments thereof, and from the accompanying
drawings.
DRAWINGS
The above-mentioned features and objects of the present disclosure
will become more apparent with reference to the following
description taken in conjunction with the accompanying drawings
wherein like reference numerals denote like elements and in
which:
FIG. 1 is perspective view of a helicopter and also showing
transmitter.
FIG. 2a is a perspective view of a co-axial type helicopter.
FIG. 2b is a perspective view of a multi-rotor copter.
FIG. 3 is a perspective view of a helicopter for showing the IRED
and IR receiving module.
FIG. 4 is a perspective view of the present disclosure showing the
helicopter hovering with altitude hold control.
FIG. 5a is a perspective view of the present disclosure showing the
helicopter having ceiling altitude hold control.
FIG. 5b is a perspective view of the present disclosure showing the
helicopter having obstacle avoidance control.
FIG. 6a shows the circuit for driving IRED.
FIG. 6b shows the voltage supply across the IRED driving circuit vs
time by assuming Imax=16.
FIG. 7 is a flow chart of altitude hold control method.
FIG. 8 is a flow chart of selectable altitude hold control
method.
FIG. 9 is the block diagram of the electronic components.
FIG. 10 is a graph relating intensity to distance.
FIG. 11 is perspective view of a helicopter and a gesture control
transmitter.
FIG. 12 is a flow chart to show the control method between the
gesture control transmitter and helicopter.
FIG. 13 is perspective view of a helicopter and another type of
gesture control transmitter.
FIG. 14 is perspective view of a full function transmitter.
DETAILED DESCRIPTION
The disclosure is capable of being implemented in embodiments in
many different forms. There are shown in the drawings and will be
described herein, in detail, some of the embodiments of the present
disclosure. The present disclosure is to be considered an
exemplification of the principles of the disclosure and is not
intended to limit the spirit or scope of the disclosure and/or the
embodiments illustrated.
The disclosure is directed to a method of controlling a flying toy
such as helicopter, the system for affecting this control and the
toy which is operable in this manner.
A method of remote controlling an altitude of a toy flying vehicle
intended for indoor operation, the vehicle having a rotor for
rotation relative to a fuselage of the vehicle, and a separate
remote controller for use by a player of the toy comprises
providing a selected altitude level for the vehicle.
A position control signal is transmitted from the vehicle towards a
surface. A receiver in the vehicle is provided for the signal
reflected from the surface.
A level of the reflected signal by the receiver is determined, and
a change of the reflected signal being an indicator of a change of
altitude of the vehicle relative to the selected altitude level.
The rotor action is adjusted in response to a change of the
altitude level thereby to retain the selected altitude level.
The selected level can be a range between an upper and a lower
level. Alternatively the level is a substantially constant
altitude.
Adjusting the rotor action is to a lower the speed to lower the
vehicle to the selected altitude level or to increase the speed to
raise the vehicle to the selected altitude level.
There is a receiver the vehicle for communication with the remote
controller, the remote controller being capable of adjusting and
controlling speed and direction of the vehicle.
The position control signal is directed upwardly thereby to retain
the altitude relative to surface located above the vehicle. The
surface from which the signal is reflected is passive indoor
surface without a signal generator feature apart from the
reflection of the position control signal. Thus there is no active
emitter on the surface, and signal bounces off a wall or ceiling or
floor which is the normal structure of an indoor environment. Thus
use of the toy does not require anything other than the flying toy
itself and the remote controller for the player.
The position control signal is directed downwardly thereby to
retain the altitude relative to surface located below the
vehicle.
Also there is a position control signal directed transversely
relative to the vehicle thereby to reflective from a transversely
located surface relative to the vehicle thereby to retain the
distance of the vehicle relative to the transversely located
surface.
There can be multiple position control signal directed transversely
in multiple respective directions relative to the vehicle thereby
to reflective from multiple transversely located surfaces relative
to the vehicle. This permits the vehicle to retain its distance
relative to the multiple transversely located surfaces, and thereby
maintain the vehicle at a selected distance relative to the
transverse surfaces.
The multiple position control signals are directed relatively
transversely, forwardly and sideways of the vehicle.
There can be multiple position control signals directed
transversely in multiple respective directions relative to the
vehicle thereby to reflective from multiple transversely located
surfaces relative to the vehicle. This retains the distance of the
vehicle relative to the multiple transversely located surfaces. The
multiple position control signals are directed relatively
transversely, forwardly and sideways of the vehicle. This maintains
the vehicle at a selected distance relative to the transverse
surfaces. The signals are directed upwardly and downwardly from the
vehicle thereby to maintain the altitude of the vehicle.
A desired selected level of reflected position control signal is
defined in at least one receiver in the vehicle. The action of the
rotor is dependent on variation from a designated position, as
determined by a difference in the received reflected position
control signal.
Respective desired selected levels of reflected position control
signals can be defined in multiple respective receivers in the
vehicle, the respective multiple receivers being directed in
respective different directions and there being multiple respective
position signals directed in mating respective directions relative
the respective receivers. The action of the rotor is dependent on
variation from designated positions, as determined by a difference
in the received reflected position control signals.
Controlling the toy can be by controls selected from at least one
of a stop control; an altitude control by at least one of an up
control; down control; a high height sensitivity control and a low
height sensitivity control. Each one of these or more of these
controls can have different degrees of sensitivity. Thus for
instance the control of the up control or down control can have a
more or a less sensitive reaction to the control button or buttons.
Thus when the flying toy is closer to a ceiling or loser to floor
the control for height may be more quickly reactive than when the
toy is further from those barriers. Appropriate control programs
are established for each of these controls protocols.
The flying toy thereby seeks to limit the maximum height thereby to
receive at least one reflected signal. Controlling rotor power can
be by current speed of rotor at a time (t) determines by previous
speed at a time (t-1), and a battery level in the flying toy.
The level of the reflected signal is a digital measure, whereby the
receiver will level whether received or not received and not an
intensity of the received the signal.
The receiver the vehicle receives throttle and direction control
command from the remote controller.
In one form the method of remote controlling an altitude of a toy
flying vehicle intended for indoor hovering flight, the vehicle
having a rotor for rotation relative to a fuselage of the vehicle,
and a separate remote controller for use by a player of the toy
comprises providing a selected altitude level for the vehicle. A
position control signal from the vehicle towards a surface. A
receiver is provided in the vehicle for the signal reflected from
the surface. A level of the reflected signal by the receiver, a
change of the reflected signal being an indicator of a change of
altitude of the vehicle relative to the selected altitude
level.
The rotor action is adjusted in response to a change of the
altitude level thereby to retain the selected altitude level;
wherein the level is a substantially constant altitude.
The vehicle is also in communication with the remote controller,
the remote controller being capable of adjusting and controlling
speed and direction of the vehicle. The receiver in the vehicle is
responsive to signals with the remote controller, and the signals
from the remote controller are for changing speed and direction of
the hovering toy.
There is provided a method of remote controlling an altitude of a
toy flying vehicle intended for indoor hovering flight, the vehicle
having a rotor for rotation relative to a fuselage of the
vehicle.
There is a separate remote controller for use by a player of the
toy.
The system comprises providing a selected altitude level for the
vehicle. A position control signal is transmitted from the vehicle
towards a surface. A receiver in the vehicle receives the signal
reflected from the surface. A level of the reflected signal by the
receiver is determined, and a change of the reflected signal is an
indicator of a change of altitude of the vehicle relative to the
selected altitude level.
The vehicle receiver communicates with the remote controller, and
the remote controller can adjust and control speed and direction of
the vehicle.
The receiver in the vehicle is responsive to signals with the
remote controller, the signals from the remote controller being for
changing speed, and also the direction of the hovering toy.
The position control signal is directed upwardly thereby to retain
the altitude relative to surface located above the vehicle, wherein
the surface from which the signal is reflected is passive indoor
surface without a signal generator feature apart from the
reflection of the position control signal. There is an additional
position control signal directed relative to the vehicle thereby to
reflective from an additional located surface relative to the
vehicle thereby to retain the distance of the vehicle relative to
the additional located surface.
While the disclosure is susceptible to embodiments in many
different forms, there are shown in the drawings and will be
described herein, in detail, the preferred embodiments of the
present disclosure. It should be understood, however, that the
present disclosure is to be considered an exemplification of the
principles of the disclosure and is not intended to limit the
spirit or scope of the disclosure and/or the embodiments
illustrated.
A toy vehicle 100 is for indoor use and is provided with a system
to control the height or distance of the vehicle away from a
surface or another object. The vehicle 100 includes a rotor 110 to
propel the vehicle 100 in a specified direction. There is a
fuselage or body 120.
In FIG. 1 there is a single rotor system for hovering toy, namely a
helicopter, and there is show a remote controller transmitter 122
with toggles 124 and 126 for controlling speed and direction of the
vehicle 100. In FIGS. 2a, 3, 4, 5a and 5b there is show a
helicopter with counter rotating rotors 128 and 129. In FIG. 2b
there is shown hovering flying toy with four spaced rotors 130,
131, 132 and 133 located about the body 120.
There is a control system and a battery power supply for the
hovering toy. The control system includes the remote controller
transmitter 122 and a receiver 134 in the body 120 which is in
wireless communication with an IR receiving module on a circuit
board 138 which is further in communication with and control of the
rotor 110. The transmitter 122 and receiver 134 pair is preferably
an infra-red pair, however other transmitter/receiver pairs or
communication protocols may be used and may be incorporated.
There is IRED cell 135 which generates a signal to a reflective
surface 136 which in turn reflects or bounces the signal back to
the receiving module 134. This signal, together with any signals
from the transmitter 122, is processed by the microprocessor
circuit MCU. The MCU in turn is powered by the battery through a
voltage regulator. The MCU controls the Gyro sensor, motor driver
control, LEDs and the power control of the hovering vehicle. The
motor drive control controls one or more motors to control one or
more rotors respectively.
The control method of the transmitter is not limited to Infrared.
It can be a radio frequency such as 27 MHz, 40 MHz, 49 MHz or 2.4
GHz, or be Bluetooth or WiFi.
The increment of light intensity I is not necessary to be increased
linearly, it can square of I .i.e I=1.sup.2, 2.sup.2, 3.sup.2, . .
. , n.sup.2 or it can be in the sequence of light intensity
decrement.
By putting the IRED and IR receiving module on top of flying toy
and applying present IR distance measurement method, it can be used
to perform an altitude hold fight with reference to ceiling of a
room rather than ground surface. (FIG. 5a).
Similarly, it can be used to detect the distance between the flying
toy and obstacles, objects or surfaces around it. By changing the
direction of flight rather than moving upward or down as in present
disclosure, it can act as obstacle avoidance control (FIG. 5b)
There can be a flying toy having plurality of rotors, infrared
emitting diode (IRED) and IR receiving module. This module can be
used to receive the signal from transmitter and the signal from the
IRED itself. In physics, the intensity or brightness of light as a
function of the distance from the light source follows an inverse
square relationship. For a given reflecting ground upper or
transverse surface and given sensitivity of IR receiving module,
the relationship between light intensity and distance can be
obtained.
Because of using light reflection method, the maximum height can be
measured is limited to less than about 3 meters.
The IR signal is usually modulated to around 30.about.40 kHz for
transmission while IR receiving module can filter the noise out of
these frequency range and demodulate the signal for MCU decoding.
The intensity of IR light that an IRED produces is directly
proportional to the current. By controlling different levels of
voltage supply and hence current to IRED, different light intensity
can be obtained.
Suppose IR intensity is denoted by I and there are Imax intensity
levels from 1, 2, . . . Imax. Also, the sensitivity of IR receiving
module is denoted by S, then the distance r is calculated by
inverse square equation
.times. ##EQU00001## where K is the characteristics of reflecting
surface. K is large for regular reflection, i.e., when a beam pass
of parallel light rays is incident on a smooth and plane surface
such as marble, mirror, gloss or white surface. K is small for
irregular reflection. i.e., when a beam of parallel light rays is
scattered in all directions. Therefore the parallel rays incident
on the surface, such as carpet, coarse or black surface, will
reflect in different directions.
Assume K remains unchanged within the same reflecting surface and S
is the constant for a given IR receiving module, the equation can
be simplified to r=K' {square root over (I)}
Since K' is unknown unless measurement is carried out on
corresponding reflecting surface, relative distance r' instead of
absolute distance can be calculated. Equation becomes
'' ##EQU00002##
The table and graph below show the relationship between light
intensity and relative distance r'
TABLE-US-00001 Light intensity Relative distance No of signals from
IRED (/) from ground (r') received (CNT) 1 1.00 16 2 1.41 15 3 1.73
14 4 2.00 13 5 2.24 12 6 2.45 11 7 2.65 10 8 2.83 9 9 3.00 8 10
3.16 7 11 3.32 6 12 3.46 5 13 3.61 4 14 3.74 3 15 3.87 2 16 4.00 1
. . . . . . . . . lmax {square root over (Imax)} lmax + 1 - 1
The altitude hold control method comprising of:
Setting the relative destination distance dest_r' from ground to be
achieved.
Initialize the light intensity I=1 and no of signals received
CNT=0.
Emitting IR signal with light intensity I to the ground surface
within the period of time between 0.4 ms to 500 ms.
Step increment of CNT if this IR signal is received by IR receiving
module. i.e CNT=CNT+1.
Step increment of light intensity i.e. I=I+1.
Repeating steps as illustrated in FIG. 7.
According to the inverse-square law, no of IR signals received
depend on the altitude of flying toy and the signal intensity. For
a given r', those signals with higher intensity can be reflected
from the ground surface to IR receiving module.
If r'=1, all IR signals can be received. i.e CNT=Imax. If r'=1.41,
only IR signals with intensity at I=2 or above can be received,
i.e. CNT=Imax-1. Similarly, if r'=1.73, only IR signals with
intensity at I=3 or above can be received, i.e. CNT=Imax-2. In
general CNT=Imax+1-I.
As CNT is known, relative distance r' can be obtained from
table.
Calculate the error E=r'-dest_r'.
If E is negative, i.e. the current altitude of the flying toy is
lower than the destination altitude, at least one of the rotors
will increase the power for flying upward in which the power
increment is proportional to E. Repeat steps as illustrated in FIG.
7.
If E is positive, i.e. the current altitude of the flying toy is
higher than the destination altitude, at least one of the rotors
will decrease the power for flying downward in which the power
decrement is proportional to E. Repeat steps as illustrated in FIG.
7.
If E is zero or approximate zero, i.e. the current altitude of the
flying toy is same as destination altitude, the power of rotors
remains unchanged. Repeat steps as illustrated in FIG. 7.
To further allow user selecting desire altitude of a flying toy,
throttle level can be read and set the relative destination
distance accordingly.
Selectable altitude hold control method comprising of:
Reading the throttle level from transmitter.
Setting the relative destination distance dest_r' from ground
according to the throttle level.
Initialize the light intensity I=1 and no of signals received
CNT=0.
Emitting IR signal with light intensity I to the ground surface
within the period of time between 0.4 ms to 500 ms.
Step increment of CNT if this IR signal is received by IR receiving
module. i.e CNT=CNT+1.
Step increment of light intensity i.e. I=I+1.
Repeating steps as illustrated in FIG. 8.
According to the inverse-square law, no of IR signals received
depend on the altitude of flying toy and the signal intensity. For
a given r', those signals with higher intensity can be reflected
from the ground surface to IR receiving module.
If r'=1, all IR signals can be received. i.e. CNT=Imax. If r'=1.41,
only IR signals with intensity at I=2 or above can be received,
i.e. CNT=Imax-1. Similarly, if r'=1.73, only IR signals with
intensity at I=3 or above can be received, i.e. CNT=Imax-2. In
general CNT=Imax+1-I.
As CNT is known, relative distance r' can be obtained from
table.
Calculate the error E=r'-dest_r'.
If E is negative, i.e. the current altitude of the flying toy is
lower than the destination altitude, at least one of the rotors
will increase the power for flying upward in which the power
increment is proportional to E. Repeat steps as illustrated in FIG.
8.
If E is positive, i.e. the current altitude of the flying toy is
higher than the destination altitude, at least one of the rotors
will decrease the power for flying downward in which the power
decrement is proportional to E. Repeat steps as illustrated in FIG.
8.
If E is zero or approximate zero, i.e. the current altitude of the
flying toy is same as destination altitude; the power of rotors
remains unchanged. Repeat steps as illustrated in FIG. 8.
In FIGS. 11 to 14 the components are 100: Helicopter; 122:
Transmitter; 601: Emergency stop button; 602a: Up button; 602b:
Down button and 603: Hi/Li sensitivity switch.
The apparatus, device, toy, system and method of operation includes
take-off/landing buttons and controls; gesture mode control; and
Left/Right trim buttons or controls. The use of any of the function
buttons can activate special features. It is possible to switch the
control method between altitude control mode and manual control
mode. The different control processes are illustrated in the flow
diagram of FIG. 12.
As illustrated in FIG. 11, apart from and in addition to a control
buttons/switch, this transmitter also includes:
1. Take-off/landing button in which the flying toy can start the
motor and fly to certain height automatically after pressing this
button. By pressing this button again, the flying toy can descend
gradually until it reaches ground level.
2. Gesture mode control in which player can tilt the transmitter
forward and backward so that the flying toy follows both direction
and speed in proportional to its tilt angle. Similarly, player can
twist the transmitter in clockwise or anti-clockwise direction so
that the flying toy can make a right or left turn in proportional
to its twist angle
3. Left and right trim buttons in which player can align the flying
toy for flying straight.
As illustrated in FIG. 13, apart from and in addition to a control
buttons/switch, this transmitter also includes:
1. Take-off/landing button in which the flying toy can start the
motor and fly to certain height automatically after pressing this
button. By pressing this button again, the flying toy can descend
gradually until it reaches ground level.
2. Gesture mode control in which player can tilt the transmitter
forward, backward, leftward or rightward so that the flying toy
follows both direction and speed in proportional to its tilt
angle.
3. Left and right trim buttons in which player can align the flying
toy for flying straight.
4. At least one function button which can be used to activate one
or more special feature on flying toy such as headlight, shooting
missile(s), taking photos or driving an actuator such as motor,
solenoid, or Shape Memory Alloy/Polymer etc.
As illustrated in FIG. 14, apart from and in addition to a control
buttons/switch, this transmitter also includes:
1. Take-off/landing button in which the flying toy can start the
motor and fly to certain height automatically after pressing this
button. By pressing this button again, the flying toy can descend
gradually until it reaches ground level.
2. One or more control sticks for controlling throttle, forward,
backward, left turn, right turn, leftward fly and rightward fly. In
manual control mode, altitude control function is masked.
3. Left and right trim buttons in which player can align the flying
toy for flying straight.
4. At least one function button which can be used to activate one
or more special feature on flying toy such as headlight, shooting
missile(s), taking photos or driving an actuator such as motor,
solenoid, or Shape Memory Alloy/Polymer etc.
5. A button or selector which can switch the control method from
manual mode to altitude control mode.
6. An operation procedure in control stick, mainly throttle stick,
which can switch the control method from altitude control mode back
to manual mode.
This operation procedure further comprises of
a. While the flying toy is in altitude control mode, release the
throttle stick so that this stick returns to neutral position by a
spring. This action does not affect the hovering height of flying
toy
b. Push the throttle stick slowly until the throttle step is
greater than or equal to current motor speed to take over the
control method from altitude control to manual control mode.
c. Indication on flying toy and/or transmitter for swapping the
control method from altitude control to manual control mode.
An alternative operation procedure comprises of
a. While the flying toy is in altitude control mode, push the
throttle stick from any region to the central region i.e. around
50% throttle
b. Keep the throttle stick in this region unchanged for a certain
period of time, says more than 1 sec.
c. Push the throttle stick either up or down slower to take over
the control method from altitude control to manual control
mode.
d. Indication on flying toy and/or transmitter for swapping the
control mode from altitude control to manual control mode.
The apparatus and method have been described in terms of what are
presently considered to be the most practical and preferred
embodiments, it is to be understood that the disclosure need not be
limited to the disclosed embodiments.
It is intended to cover various modifications and similar
arrangements included within the spirit and scope of the claims,
the scope of which should be accorded the broadest interpretation
so as to encompass all such modifications and similar structures.
The present disclosure includes any and all embodiments of the
following claims.
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